Why we should step in to halt bad behaviour

My wife thinks I'll get stabbed one day. She thinks I get too angry about things I should let pass; she suspects that offering advice to those failing to observe basic social niceties is more provocative than helpful. She's not sure what I achieve by asking people to pick up their litter, or grabbing shoplifters, or asking a man in the doorway of McDonald's to stop hitting his girlfriend.

Part of me thinks she's right, and that my blood pressure would fall if I turned away. But then another side - for the sake of argument, let's call it a conscience - kicks in. The things I get mad about diminish our society and lower the quality of life. Isn't it my duty to pipe up? In fact, shouldn't more people intervene? After all, isn't the wellbeing of society the responsibility of the whole of society?

It turns out I'm not alone. The thinktank Reform says Britons are too ready to abdicate responsibility for dealing with wrongdoing - that we have "nationalised and politicised" antisocial behaviour to such an extent that we have become a "nation of bystanders": six out of 10 of us would not step in to stop a group of teenage vandals. We think our duties end with calling the police; in other European countries tackling antisocial behaviour is seen as everyone's responsibility.

We do turn our backs because - like my wife - we believe the likely consequence of any intervention will be a stabbing. This despite the British Crime Survey showing that knife crime has remained stable over the past decade, and a Metropolitan Police survey showing that knife crime in London has actually dropped over the past two years, by a startling 15.7%.

The saddest thing for those of us who believe it is right to intervene is that we get branded as rightwing, law-and-order-obsessed vigilantes. In fact, we're trying to uphold the classic leftwing value: that we are all responsible for the society we live in. It's not, whatever David Cameron might say, the Labour government to blame for the I'll-do-what-I-want culture that most of us blame for antisocial behaviour. After all, it wasn't a Labour prime minister who said, "There's no such thing as society," was it?